The primary task of light devices of motor vehicles is to light the carriageway or to emit light signal functions. However, at present there is an increasing focus on significantly higher involvement of headlights and signal lamps in the designer concept of the vehicle. Light devices should not only emit light with the required radiation characteristic, but at the same time they should participate in the character of the vehicle.
A signal lamp, especially one for motor vehicles, contains multiple lighting units wherein each of these lighting units provides a different light function or contributes to ensuring the required emission characteristic of the light trace. Individual lighting units are generally mounted in a shaped carrying bushing of the lamp, wherein each unit contains at least one light source and other optical elements. The light source emits light rays and the optical elements represent a system of refractive and reflective surfaces and interfaces of optical environments that influence the direction of light rays within the creation of the output light trace.
A number of lighting devices are known from the prior art that are adapted to create various patterns and spatial effects. E.g. the document EP1126209 discloses a lighting device comprising a light guiding optical element adapted to combine the light generated by two different light sources, the device making it possible to emit a different light pattern in the lit state. A disadvantage of the above mentioned solution consists in limited designer options because designer requirements for the external appearance of the product cannot be met, e.g. it cannot actively create light patterns with a spatial effect in the lit state and in the off state, when the optical elements do not provide a spatial impression. The device does not support creation of 3D effects after switching off of the light source, e.g. in the form of spatially arranged crystals.
The documents CZ20150002 discloses the design of a signal lamp that comprises a spatially shaped light guide the parts of which, especially the output surfaces, overlap each other in the view of the inner space of the headlight, which makes it possible to produce a spatial effect, e.g. in the form of spatially arranged crystals, even after the light source being switched off. A disadvantage of this design is the fact that the spatially shaped light guide occupies a considerable installation space, is expensive to produce and does not allow more light functions to be combined.
The document FR2758874 discloses a lighting device that makes it possible to create a spatial effect through a combination of two differently colored materials, which supports better effects of the external appearance of the product even in the off state, i.e. when the light source has been switched off. The document FR2965328 discloses a lighting and/or signaling device comprising more optical elements situated in the inner space of the lamp, creating one complex part with an externally situated light guide. Individual optical elements can be made of a translucent or transparent or reflective or diffusive, or opaque or fluorescent or metal-plated material, wherein individual optical elements can be shaped in any way to ensure an optimum optical performance. A disadvantage of this device consists in high requirements for the installation space inside the light device.
An optical concept making it possible to combine more light functions and/or light from more light units is known from the document EP1950492. The document DE102011111994 discloses a light device in the form of a light disk that contains two layers adjacent to each other. The first body/layer is made of a transparent material and is adapted to conduct light, being fitted with light guides to emit light in the required direction. The other body/layer is created as a semi-transparent plate fitted with multiple openings the light guides of the first body lead into. The other body creates a light scattering area between the openings so that the light emitted by the first body can be bound to the other body and can pass through this other body to be subsequently scattered on its diffusion surface. The document WO2006082081 discloses a lighting device containing light sources whose light is emitted towards a diffusion layer containing plastic dispersion elements, the diffusion layer being a part of the outer housing of the lighting device. A disadvantage of the above mentioned solutions is the fact that the optical concepts are not adaptable to designer requirements for the external appearance of the product as the lighting device should participate in the character of the vehicle and produce certain impressions. They do not make it possible to combine more light functions from different lighting means, either.
The objective of the invention is to design a light device, especially a signal lamp for motor vehicles, that can be adapted to designer requirements for the external appearance of the product, wherein the light device should, besides emitting light, participate in the designer character of the vehicle. In the off state, a spatial impression should be maintained and the device must offer the possibility to create light effects, e.g. in the form of spatially arranged crystals. The optical concept must not occupy a large installation space, and the light device must not be expensive to produce, and must make it possible to combine more light functions and/or to use light from more light means.